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Euler Programming Language
Euler is a programming language created by Niklaus Wirth and Helmut Weber, conceived as an extension and generalization of ALGOL 60. The designers' goals were to create a language that is: * Simpler, yet more flexible, than ALGOL 60 * Useful and processed with reasonable efficiency * Definable with Formal methods, rigorous formality Available sources indicate that Euler was operational by 1965. Overview Euler employs a general data type concept. In Euler, Array data type, arrays, Subroutine, procedures, and switches are not quantities which are declared and named by identifiers: in contrast to ALGOL, they are not quantities on the same level as Variable (computer science), variables. Rather, these quantities are on the level of numeric and boolean Constant (computer programming), constants. Thus, besides the traditional numeric and logical constants, Euler introduces several added types: * Reference * Label (programming language), Label * Symbol (programming), Symbol * List (arr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multi-paradigm Programming Language
Programming paradigms are a way to classify programming languages based on their features. Languages can be classified into multiple paradigms. Some paradigms are concerned mainly with implications for the execution model of the language, such as allowing side effects, or whether the sequence of operations is defined by the execution model. Other paradigms are concerned mainly with the way that code is organized, such as grouping a code into units along with the state that is modified by the code. Yet others are concerned mainly with the style of syntax and grammar. Common programming paradigms include: * imperative in which the programmer instructs the machine how to change its state, ** procedural which groups instructions into procedures, ** object-oriented which groups instructions with the part of the state they operate on, * declarative in which the programmer merely declares properties of the desired result, but not how to compute it ** functional in which the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formal Methods
In computer science, formal methods are mathematically rigorous techniques for the specification, development, and verification of software and hardware systems. The use of formal methods for software and hardware design is motivated by the expectation that, as in other engineering disciplines, performing appropriate mathematical analysis can contribute to the reliability and robustness of a design. Formal methods employ a variety of theoretical computer science fundamentals, including logic calculi, formal languages, automata theory, control theory, program semantics, type systems, and type theory. Background Semi-Formal Methods are formalisms and languages that are not considered fully “formal”. It defers the task of completing the semantics to a later stage, which is then done either by human interpretation or by interpretation through software like code or test case generators. Taxonomy Formal methods can be used at a number of levels: Level 0: Formal specification may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wirth–Weber Precedence Relationship
In computer science, a ''Wirth–Weber relationship'' between a pair of symbols (V_t \cup V_n) is necessary to determine if a formal grammar is a simple precedence grammar. In such a case, the simple precedence parser can be used. The relationship is named after computer scientists Niklaus Wirth Niklaus Emil Wirth (born 15 February 1934) is a Swiss computer scientist. He has designed several programming languages, including Pascal (programming language), Pascal, and pioneered several classic topics in software engineering. In 1984, he w ... and Helmut Weber. The goal is to identify when the viable prefixes have the ''pivot'' and must be reduced. A \gtrdot means that the ''pivot'' is found, a \lessdot means that a potential ''pivot'' is starting, and a \doteq means that a relationship remains in the same ''pivot''. Formal definition : G = \langle V_n, V_t, S, P \rangle :: \begin X \doteq Y &\iff \begin A \to \alpha X Y \beta \in P \\ A \in V_n \\ \alpha , \beta \in (V_n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamic Typing
In computer programming, a type system is a logical system comprising a set of rules that assigns a property called a type to every "term" (a word, phrase, or other set of symbols). Usually the terms are various constructs of a computer program, such as variables, expressions, functions, or modules. A type system dictates the operations that can be performed on a term. For variables, the type system determines the allowed values of that term. Type systems formalize and enforce the otherwise implicit categories the programmer uses for algebraic data types, data structures, or other components (e.g. "string", "array of float", "function returning boolean"). Type systems are often specified as part of programming languages and built into interpreters and compilers, although the type system of a language can be extended by optional tools that perform added checks using the language's original type syntax and grammar. The main purpose of a type system in a programming language ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbol (programming)
A symbol in computer programming is a primitive data type whose instances have a unique human-readable form. Symbols can be used as identifiers. In some programming languages, they are called atoms. Uniqueness is enforced by holding them in a symbol table. The most common use of symbols by programmers is for performing language reflection (particularly for callbacks), and most common indirectly is their use to create object linkages. In the most trivial implementation, they are essentially named integers (e.g. the enumerated type in C). Support The following programming languages provide runtime support for symbols: Julia Symbols in In Julia, are interned strings used to represent identifiers in parsed julia code( ASTs) and as names or labels to identify entities (for example as keys in a dictionary). Lisp A symbol in Lisp is unique in a namespace (or ''package'' in Common Lisp). Symbols can be tested for equality with the function EQ. Lisp programs can generate new s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Label (programming Language)
In programming languages, a label is a sequence of characters that identifies a location within source code. In most languages, labels take the form of an identifier, often followed by a punctuation character (e.g., a colon). In many high-level languages, the purpose of a label is to act as the destination of a GOTO statement. In assembly language, labels can be used anywhere an address can (for example, as the operand of a JMP or MOV instruction). Also in Pascal and its derived variations. Some languages, such as Fortran and BASIC, support numeric labels. Labels are also used to identify an entry point into a compiled sequence of statements (e.g., during debugging In computer programming and software development, debugging is the process of finding and resolving '' bugs'' (defects or problems that prevent correct operation) within computer programs, software, or systems. Debugging tactics can involve in ...). C In C (programming language), C a label identifies a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |